Add API endpoint to retrieve custom languages and complete language pack

include/I18n.h

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#pragma once
+
+#include <TaskSchedulerDeclarations.h>
+#include <WString.h>
+#include <list>
+
+struct LanguageInfo_t {
+    String code;
+    String name;
+    String filename;
+};
+
+class I18nClass {
+public:
+    I18nClass();
+    void init(Scheduler& scheduler);
+    std::list<LanguageInfo_t> getAvailableLanguages();
+
+private:
+    void readLangPacks();
+    void readConfig(String file);
+
+    std::list<LanguageInfo_t> _availLanguages;
+};
+
+extern I18nClass I18n;

include/Utils.h

@@ -11,4 +11,5 @@ public:
     static int getTimezoneOffset();
     static bool checkJsonAlloc(const JsonDocument& doc, const char* function, const uint16_t line);
     static void removeAllFiles();
+    static String generateMd5FromFile(String file);
 };

include/WebApi.h

@@ -9,6 +9,7 @@
 #include "WebApi_file.h"
 #include "WebApi_firmware.h"
 #include "WebApi_gridprofile.h"
+#include "WebApi_i18n.h"
 #include "WebApi_inverter.h"
 #include "WebApi_limit.h"
 #include "WebApi_maintenance.h"
@@ -53,6 +54,7 @@ private:
     WebApiFileClass _webApiFile;
     WebApiFirmwareClass _webApiFirmware;
     WebApiGridProfileClass _webApiGridprofile;
+    WebApiI18nClass _webApiI18n;
     WebApiInverterClass _webApiInverter;
     WebApiLimitClass _webApiLimit;
     WebApiMaintenanceClass _webApiMaintenance;

include/WebApi_i18n.h

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#pragma once
+
+#include <ESPAsyncWebServer.h>
+#include <TaskSchedulerDeclarations.h>
+
+class WebApiI18nClass {
+public:
+    void init(AsyncWebServer& server, Scheduler& scheduler);
+
+private:
+    void onI18nLanguages(AsyncWebServerRequest* request);
+    void onI18nLanguage(AsyncWebServerRequest* request);
+};

include/defaults.h

@@ -108,3 +108,5 @@
 #define LED_BRIGHTNESS 100U
 
 #define MAX_INVERTER_LIMIT 2250
+
+#define LANG_PACK_SUFFIX ".lang.json"